Rat Brains Get an Upgrade

At Universitat Tel Aviv in Israel, scientists have successfully engineered and implanted an artificial cerebellum into the brain of a rat. Designed by Dr. Matti Mintz, it is a microchip attached to the rat’s head that receives sensory information from the brain stem and sends it to other parts of the brain. The artificial cerebellum has successfully restored lost brain function in rats.

There have been devices for a while now that work by one way electrical communication with the brain such as cochlear and retinal implants. This device is a breakthrough because it receives an input directly from the brain, analyzes it much like an actual neural network, and then sends the information back to the brain in a decipherable code. One major function of the cerebellum is to precisely time and coordinate movements, necessitating the pairing of the neuronal input and output. Since the architecture of the cerebellum is well known, it is a relatively simple region of the brain to replicate.

The chip that sits outside the skull is wired into the brain using electrodes. Mintz and his colleagues extensively characterized the neuronal communication between intact brainstem-cerebellum circuits to precisely program the chip to behave identically.

To test the chip, Mintz’s team anaesthetised a rat and disabled its cerebellum to hook up their own version. With the chip disconnected, the rat was unable to learn a conditioned motor reflex; in this case, the team combined a tone with a puff of air into the eye so that the rat would blink on only hearing the tone. However, once the chip was connected, the rat behaved normally and blinked in response to the puff.

As a proof of concept, the chip demonstrates how close we are to creating circuitry to mimic or even enhance parts of the brain. Even though the chip only mimics a very basic function it opens up doors to immense possibilities. The next step is to model a larger area of the cerebellum, perhaps a section that can learn a sequence of movements rather than just one, and to to test that on a conscious animal. The ultimate goal then being to duplicate any of the complex parts of the brain which could be a potent means to treat brain damage as opposed to more tradiotional biological or surgical methods.